An Istanbul court on Tuesday ruled that five Cumhuriyet daily journalists must remain in custody pending trial on serious terrorism-related charges.

During the hearing at the Istanbul 27th High Criminal Court, a total of 20 suspects, five of whom are currently in jail, were on trial to face terror charges against them.

Two of the suspects including the daily's former editor-in-chief Can Dündar are fugitives.

The Court ruled that five defendants, including Cumhuriyet editor-in-chief Murat Sabuncu, journalist Ahmet Şık and CEO Akin Atalay will remain in jail.

The suspects are charged with aiding and abetting the PKK, Gülenist terror group (FETÖ) and leftist DHKP/C terrorist organizations.

Prison sentences requested by the state prosecution ranged from seven-and-a-half years to 43 years.

The court began its first hearing in the case on July 24; the next hearing is expected to take place in late December.

The PKK is listed as a terrorist organization by Turkey, the U.S., and EU and has been responsible for the deaths of more than 1,200 people since July 2015.

FETÖ and its Pennsylvania-based leader Fetullah Gülen orchestrated last year's July 15 defeated coup attempt which left 250 people martyred, and nearly 2,200 injured. The terror group is also behind of a years-long infiltration against Turkish institutions -- particularly the military, police, and judiciary -- to form what is commonly known as a parallel state.